Two moles of an ideal gas expand freely and isothermally from $5 \ dm^3$ to $50 \ dm^3$. What is the value of $\Delta H$?

Identify the intensive quantity from the following.

In an exothermic reaction,the reactants:

$2$ moles of an ideal gas expands isothermally from $5$ $dm^3$ to $10$ $dm^3$ at a constant external pressure of $1.5$ bar. Calculate the work done.

Work done when $2 \ mol$ of an ideal gas is compressed from a volume of $5 \ m^{3}$ to $2.5 \ m^{3}$ at $300 \ K$, under a constant external pressure of $100 \ kPa$ is: (in $kJ$)

Identify the equation in which the change in enthalpy is equal to the change in internal energy.